> The -enable-checking configure code in libcody didn't play well with
> us.  This just uses libcpp's configurey for that piece.

This doesn't set is_release anywhere, which means when --enable-checking*
or --disable-checking isn't specified, it always treats it as
--enable-checking=yes, while the normal gcc behavior is treat only trunk
as --enable-checking=yes and treat release branches as
--enable-checking=release by default.

On the other side, nothing uses those ac_assert_checking and
ac_valgrind_checking variables, so it is a waste to compute those.

2020-12-16  Jakub Jelinek  <jakub@redhat.com>

	* configure.ac: Compute is_release.
	(NMS_ENABLE_CHECKING): Simplify but not computing ac_assert_checking
	and ac_valgrind_checking the code doesn't use.
	* configure: Regenerated.

Reject DATA elements with the ALLOCATABLE attribute also when they are
components of a derived type.

gcc/fortran/ChangeLog:

	PR fortran/98284
	* resolve.c (check_data_variable): Reject DATA elements with the
	ALLOCATABLE attribute.

gcc/testsuite/ChangeLog:

	PR fortran/98284
	* gfortran.dg/pr98284.f90: New test.

The SECTION_LINK_ORDER changes don't seem to work properly.

If I compile:
static inline __attribute__((__gnu_inline__)) __attribute__((__unused__)) __attribute__((patchable_function_entry(0, 0))) int foo (int x)
{
  return x + 1;
}

static inline __attribute__((__gnu_inline__)) __attribute__((__unused__)) __attribute__((patchable_function_entry(0, 0))) int bar (int x)
{
  return x + 2;
}

int
baz (int x)
{
  return foo (x) + 1;
}

int
qux (int x)
{
  return bar (x) + 2;
}
(distilled from aarch64 Linux kernel) with
-O2 -fpatchable-function-entry=2 on aarch64 compiler configured against
latest binutils, I get:
...
	.section	__patchable_function_entries,"awo",@progbits,baz
...
	.section	__patchable_function_entries
...
in the assembly, but when it is assembled, one gets:
  [ 4] __patchable_function_entries PROGBITS        0000000000000000 000060 000008 00 WAL  1   0  8
  [ 5] .rela__patchable_function_entries RELA            0000000000000000 000280 000018 18   I 12   4  8
  [ 6] __patchable_function_entries PROGBITS        0000000000000000 000068 000008 00      0   0  8
  [ 7] .rela__patchable_function_entries RELA            0000000000000000 000298 000018 18   I 12   6  8
i.e. one writable allocated section with SHF_LINK_ORDER and another
non-allocated non-writable without link order.  In the kernel case there is
always one entry in the WAL section and then dozens or more in the
non-allocated one.
The kernel then fails to link:
WARNING: modpost: vmlinux.o (__patchable_function_entries): unexpected non-allocatable section.
Did you forget to use "ax"/"aw" in a .S file?
Note that for example <linux/init.h> contains
section definitions for use in .S files.
ld: .init.data has both ordered [`__patchable_function_entries' in init/main.o] and unordered [`.init.data' in
+./drivers/firmware/efi/libstub/vsprintf.stub.o] sections
ld: final link failed: bad value
make: *** [Makefile:1175: vmlinux] Error 1

The following patch fixes it by always forcing full section flags for
SECTION_LINK_ORDER sections.

2020-12-16  Jakub Jelinek  <jakub@redhat.com>

	* varasm.c (default_elf_asm_named_section): Always force
	section flags even for sections with SECTION_LINK_ORDER flag.

Before CWG DR 1955 the controlling expression for an #elif must be
syntactically correct, meaning this won't compile with C++11 compilers
such as gcc 4.8:

The solution is to define __has_include(X) as 0 for compilers that don't
support it.

The second problem is that when <source_location> is found, it is used
without the std:: qualification.

libcody/ChangeLog:

	* internal.hh: Define fallback macros for __has_builtin and
	__has_include. Use __has_builtin for __builtin_FILE and
	__builtin_LINE. Define alias for std::source_location.

Clang doesn't support __builtin_sprintf, so use std::sprintf instead.

libstdc++-v3/ChangeLog:

	PR libstdc++/96083
	* include/ext/throw_allocator.h: Use __has_builtin to check for
	__builtin_sprintf support, and use std::sprtinf if necessary.

The -enable-checking configure code in libcody didn't play well with
us.  This just uses libcpp's configurey for that piece.

	libcody/
	* configure.ac: Use libcpp's enable-checking code.
	* configure: Rebuilt.

There were still some dash-killing uses of +=.  Fixed thusly.

	* config.m4: Replace V+="..." with V="$V..."
	* configure: Rebuilt.

module.cc has a static initializer that ends up in a circular
dependency when detailed mem stats are enabled.  This removes the need
for that initializer to be dynamic, and we punt to the lazy
initializing we already had inside the object in question anyway.  At
the cost of an additional indirection.

	gcc/cp/
	* module.cc (loc_spans): Make spans a pointer, not inline.
	Adjust all accesses.

Since SHF_GNU_RETAIN support doesn't work for crtstuff.c which switches
the output section directly with asm statement:

---
static void __attribute__((used))
__do_global_dtors_aux (void)
{
  static _Bool completed;

  if (__builtin_expect (completed, 0))
    return;
  completed = 1;
}

static void __attribute__((__used__))
call___do_global_dtors_aux (void)
{
  asm ("\t.section\t.fini");
  __do_global_dtors_aux ();
  asm ("\t.section\t.text");
}
---

use SHF_GNU_RETAIN only if .init_array/.fini_array section is supported.

gcc/

	PR target/98146
	* defaults.h (SUPPORTS_SHF_GNU_RETAIN): New.
	* varasm.c (get_section): Replace HAVE_GAS_SHF_GNU_RETAIN with
	SUPPORTS_SHF_GNU_RETAIN.
	(resolve_unique_section): Likewise.
	(get_variable_section): Likewise.
	(switch_to_section): Likewise.

gcc/testsuite/

	PR target/98146
	* lib/target-supports.exp
	(check_effective_target_R_flag_in_section): Also check
	HAVE_INITFINI_ARRAY_SUPPORT != 0.

When SECTION_RETAIN is used, issue a warning when a symbol without used
attribute and a symbol with used attribute are placed in the section with
the same name, like

int __attribute__((used,section(".data.foo"))) foo2 = 2;
int __attribute__((section(".data.foo"))) foo1 = 1;

since assembler will put them in different sections with the same section
name.

gcc/

	PR target/98146
	* varasm.c (switch_to_section): Warn when a symbol without used
	attribute and a symbol with used attribute are placed in the
	section with the same name.

gcc/testsuite/

	PR target/98146
	* c-c++-common/attr-used-5.c: Updated.
	* c-c++-common/attr-used-6.c: Likewise.
	* c-c++-common/attr-used-7.c: Likewise.
	* c-c++-common/attr-used-8.c: Likewise.

When definitions marked with used attribute and unmarked definitions are
placed in the section with the same name, switch to a new section if the
SECTION_RETAIN bit doesn't match.

gcc/

	PR target/98146
	* output.h (switch_to_section): Add a tree argument, default to
	nullptr.
	* varasm.c (get_section): If the SECTION_RETAIN bit doesn't match,
	return and switch to a new section later.
	(assemble_start_function): Pass decl to switch_to_section.
	(assemble_variable): Likewise.
	(switch_to_section): If the SECTION_RETAIN bit doesn't match,
	switch to a new section.

gcc/testsuite/

	PR target/98146
	* c-c++-common/attr-used-5.c: New test.
	* c-c++-common/attr-used-6.c: Likewise.
	* c-c++-common/attr-used-7.c: Likewise.
	* c-c++-common/attr-used-8.c: Likewise.
	* c-c++-common/attr-used-9.c: Likewise.

Currently the <experimental/random>, <experimental/source_location> and
<experimental/utility> headers can be included in C++98 and C++11 modes,
but gives errors. With this change they can be included, but define
nothing.

libstdc++-v3/ChangeLog:

	PR libstdc++/98319
	* include/experimental/random: Only define contents for C++14
	and later.
	* include/experimental/source_location: Likewise.
	* include/experimental/utility: Likewise.
	* testsuite/experimental/feat-lib-fund.cc: Include all LFTS
	headers that are present. Allow test to run for all modes.

This adds a test to compare the performance of std::atomic_flag with
similar operations on std::atomic_uchar and std::atomic_int.

libstdc++-v3/ChangeLog:

	PR libstdc++/46447
	* testsuite/performance/29_atomics/atomic_flag.cc: New test.

This fixes a bug caused by a mismatch between the macros defined by
<errno.h> when GCC is built and the macros defined by <errno.h> when
users include <system_error>. If the user code is compiled with
_XOPEN_SOURCE defined to 500 or 600, Darwin suppresses the
ENOTRECOVERABLE and EOWNERDEAD macros, which are not defined by SUSv3
(aka POSIX.1-2001).

Since POSIX requires the errno macros to be macros (and not variables or
enumerators) we can just test for them directly using the preprocessor.
That means that <system_error> will match what is actuallydefined when
it's included, not what was defined when GCC was built. With that change
there is no need for the GLIBCXX_CHECK_SYSTEM_ERROR configure checks and
they can be removed.

libstdc++-v3/ChangeLog:

	PR libstdc++/93151
	* acinclude.m4 (GLIBCXX_CHECK_SYSTEM_ERROR): Remove.
	* configure.ac: Regenerate.
	* config/os/generic/error_constants.h: Test POSIX errno macros
	directly, instead of corresponding _GLIBCXX_HAVE_EXXX macros.
	* testsuite/19_diagnostics/headers/system_error/errc_std_c++0x.cc:
	Likewise.
	* testsuite/19_diagnostics/headers/system_error/93151.cc: New
	test.

This fixes installers that don't understand -p.

	c++tools/
	* Makefile.in (install): Do not use -p, use mkinstalldirs.
	(clean): Fix typo.

Solaris' sys/socket uses the poisoned bcopy identifier, so we must
preemptively copy a bit of cody's inclusion logic to get it earlier.

	gcc/cp/
	* mapper-client.cc: Include sys/socket.h before system.h.

gcc/ada/

	* ali.ads, ali.adb, bindo-writers.adb, lib-writ.adb (Scope):
	Renamed to IS_Scope.

gcc/ada/

	* libgnat/a-strfix.ads: Add postconditions and contract cases to
	subprograms.

gcc/ada/

	* sem_ch5.adb (Analyze_Iterator_Specification): If iterator
	filter is present, preanalyze filter without expansion.
	(Analyze_Loop_Parameter_Specification): When
	loop_Parameter_Specification is rewritten as
	Iterator_Specification, transfer Iterator_Filter if present.

gcc/ada/

	* libgnat/s-objrea.ads (Object_Arch): Add ARM enum
	* libgnat/s-objrea.adb (Initialize): Add EM_ARM case.
	(Read_Address): Add ARM case to 32bit read.
	* Makefile.rtl: Add trasym units to the runtime for armhf-linux.

gcc/ada/

	* libgnat/g-expect.adb (Non_Blocking_Spawn): Deallocate elements
	on Arg_List after calling Set_Up_Child_Communications.

gcc/ada/

	* par-ch3.adb (P_Modular_Type_Definition): Remove colon from
	error message.
	* sem_ch11.adb (Check_Duplication): Likewise.
	* sem_ch3.adb (Derived_Type_Declaration): Likewise.

gcc/ada/

	* par-ch12.adb (P_Formal_Object_Declarations): Refine types to
	Pos.

gcc/ada/

	* impunit.adb (Not_Impl_Defined_Unit): Fix typo in iteration
	over Non_Imp_File_Names_12 array.

gcc/ada/

	* exp_ch9.adb, sem_warn.adb: Simplify membership test.

gcc/ada/

	* exp_ch6.adb, exp_util.adb, sem_ch4.adb, sem_disp.adb,
	sem_elab.adb: Simplify membership test.

gcc/ada/

	* libgnat/s-powtab.ads (Maxpow): Use explicit formula in comment.

gcc/ada/

	* libgnarl/s-tporft.adb (Register_Foreign_Thread): Set
	Global_Task_Lock_Nesting before using allocator.

gcc/ada/

	* libgnat/s-valrea.adb (Maxexp32): New constant array.
	(Maxexp64): Likewise.
	(Maxexp80): Likewise.
	(Integer_to_Real): New local constants Maxexp and B.
	When the exponent is too negative, do the divison in two steps.

gcc/ada/

	* doc/gnat_rm/implementation_defined_pragmas.rst
	(Test_Case): Change integer to float literals.
	* gnat_rm.texi: Regenerate.

gcc/ada/

	* sem_ch13.adb (Analyze_Aspect_Specifications): Add a codefix
	for extra parentheses around aspect Annotate expression; reject
	"(null record)" aggregate and extra parentheses around aspect
	Test_Case expression.
	* sem_prag.adb (Analyze_Pragma): Reject "null", "(null record)"
	and extra parentheses around pragma Contract_Cases; likewise for
	pragma Subprogram_Variant.

gcc/ada/

	* adaint.h (__gnat_in_child_after_fork): New flag to express
	child process side after fork call.
	* adaint.c (__gnat_portable_spawn): Set flag
	__gnat_in_child_after_fork.
	* expect.c (__gnat_expect_fork): Set __gnat_in_child_after_fork
	to one on child side.
	* libgnat/memtrack.adb
	(In_Child_After_Fork): Flag to disable memory tracking.
	(Allow_Trace): New routine defining if memory should be tracked.
	(Alloc, Realloc, Free): Use Allow_Trace in "if" condition
	instead of First_Call.

gcc/ada/

	* libgnat/a-tifiio.adb: Mark body not in SPARK.
	* libgnat/a-tifiio.ads: Mark spec in SPARK.
	* libgnat/a-tifiio__128.adb: Mark body not in SPARK.

gcc/ada/

	* libgnat/s-valuer.adb (Scan_Decimal_Digits): Tweak overflow test.
	(Scan_Integral_Digits): Likewise.

gcc/ada/

	* s-oscons-tmplt.c: Add some OS constants.

The following patch teaches the bswap pass to handle for small (2/4/8 byte
long) vectors a CONSTRUCTOR by determining if the bytes of the constructor
come from non-vector sources and are either nop or bswap and changing the
CONSTRUCTOR in that case to VIEW_CONVERT_EXPR from scalar integer to
the vector type.

Unfortunately, as I found after the patch was written, due to pass ordering
this doesn't really fix the original testcase, just the one I wrote,
because both loop and slp vectorization is done only after the bswap pass.
A possible way out of that would be to perform just this particular bswap
optimization (i.e. for CONSTRUCTOR assignments with integral vector types
call find_bswap_or_nop and bswap_replace if successful) also during the
store merging pass, it isn't really a store, but the store merging pass
already performs bswapping when handling store, so it wouldn't be that big
hack.  What do you think?

2020-12-16  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/96239
	* gimple-ssa-store-merging.c (find_bswap_or_nop): Handle a vector
	CONSTRUCTOR.
	(bswap_replace): Likewise.

	* gcc.dg/pr96239.c: New test.

gcc/brig/ChangeLog:

	* lang.opt: Remove usage of Report.

gcc/c-family/ChangeLog:

	* c.opt: Remove usage of Report.

gcc/ChangeLog:

	* common.opt: Remove usage of Report.
	* config/aarch64/aarch64.opt: Ditto.
	* config/alpha/alpha.opt: Ditto.
	* config/arc/arc.opt: Ditto.
	* config/arm/arm.opt: Ditto.
	* config/avr/avr.opt: Ditto.
	* config/bfin/bfin.opt: Ditto.
	* config/bpf/bpf.opt: Ditto.
	* config/c6x/c6x.opt: Ditto.
	* config/cr16/cr16.opt: Ditto.
	* config/cris/cris.opt: Ditto.
	* config/cris/elf.opt: Ditto.
	* config/csky/csky.opt: Ditto.
	* config/darwin.opt: Ditto.
	* config/fr30/fr30.opt: Ditto.
	* config/frv/frv.opt: Ditto.
	* config/ft32/ft32.opt: Ditto.
	* config/gcn/gcn.opt: Ditto.
	* config/i386/cygming.opt: Ditto.
	* config/i386/i386.opt: Ditto.
	* config/ia64/ia64.opt: Ditto.
	* config/ia64/ilp32.opt: Ditto.
	* config/linux-android.opt: Ditto.
	* config/linux.opt: Ditto.
	* config/lm32/lm32.opt: Ditto.
	* config/m32r/m32r.opt: Ditto.
	* config/m68k/m68k.opt: Ditto.
	* config/mcore/mcore.opt: Ditto.
	* config/microblaze/microblaze.opt: Ditto.
	* config/mips/mips.opt: Ditto.
	* config/mmix/mmix.opt: Ditto.
	* config/mn10300/mn10300.opt: Ditto.
	* config/moxie/moxie.opt: Ditto.
	* config/msp430/msp430.opt: Ditto.
	* config/nds32/nds32.opt: Ditto.
	* config/nios2/elf.opt: Ditto.
	* config/nios2/nios2.opt: Ditto.
	* config/nvptx/nvptx.opt: Ditto.
	* config/pa/pa.opt: Ditto.
	* config/pdp11/pdp11.opt: Ditto.
	* config/pru/pru.opt: Ditto.
	* config/riscv/riscv.opt: Ditto.
	* config/rl78/rl78.opt: Ditto.
	* config/rs6000/aix64.opt: Ditto.
	* config/rs6000/linux64.opt: Ditto.
	* config/rs6000/rs6000.opt: Ditto.
	* config/rs6000/sysv4.opt: Ditto.
	* config/rx/elf.opt: Ditto.
	* config/rx/rx.opt: Ditto.
	* config/s390/s390.opt: Ditto.
	* config/s390/tpf.opt: Ditto.
	* config/sh/sh.opt: Ditto.
	* config/sol2.opt: Ditto.
	* config/sparc/long-double-switch.opt: Ditto.
	* config/sparc/sparc.opt: Ditto.
	* config/tilegx/tilegx.opt: Ditto.
	* config/tilepro/tilepro.opt: Ditto.
	* config/v850/v850.opt: Ditto.
	* config/visium/visium.opt: Ditto.
	* config/vms/vms.opt: Ditto.
	* config/vxworks.opt: Ditto.
	* config/xtensa/xtensa.opt: Ditto.

gcc/lto/ChangeLog:

	* lang.opt: Remove usage of Report.

Since g:7caa4970 the option is ignored
as we print used command line for -fverbose-asm output.

gcc/ChangeLog:

	* doc/options.texi: Remove Report keyword.
	* opt-functions.awk: Print error when Report keyword
	is used.
	* optc-gen.awk: Do not handle Report keyword.
	* opts.h (struct cl_option): Remove cl_report bitfield flag.

gcc/ChangeLog:

	PR sanitizer/97868
	* common.opt: Add new warning -Wtsan.
	* doc/invoke.texi: Likewise.
	* tsan.c (instrument_builtin_call): Warn users about unsupported
	std::atomic_thread_fence.

gcc/testsuite/ChangeLog:

	PR sanitizer/97868
	* gcc.dg/tsan/atomic-fence.c: New test.

gcc/ChangeLog:

	PR rtl-optimization/98271
	PR rtl-optimization/98276
	PR tree-optimization/98279
	* opts-common.c (set_option): Do not allow overflow for integer
	arguments.

gcc/testsuite/ChangeLog:

	PR rtl-optimization/98271
	PR rtl-optimization/98276
	PR tree-optimization/98279
	* gcc.dg/pr98271.c: New test.